On Tue, Jun 12, 2018 at 07:01:59PM +0200, Christophe LEROY wrote: > > > Le 12/06/2018 à 16:53, Segher Boessenkool a écrit : > >On Tue, Jun 12, 2018 at 09:14:53AM +0000, Christophe Leroy wrote: > >>--- > >>Not tested on PPC64. > > > >It won't be acceptable until that happens. It also is likely quite bad > >performance on all 64-bit CPUs from the last fifteen years or so. Or you > >did nothing to prove otherwise, at least. > > Will it be as bad as the generic implementation which does it byte per > byte ?
Probably not. But how is it for short inputs, etc.? The main point is that it needs actual testing _for correctness_. Btw, GCC 7 and later can expand many memcmp as builtins on PowerPC (just like memset and memcpy etc.), creating better code, without function call. Segher
